A 64-year-old woman presents for evaluation of recent loss o…
A 64-year-old woman presents for evaluation of recent loss of appetite, abdominal cramps, constipation, and “bright red blood” in her stool. The patient reports that she was in good health until approximately 6 weeks ago, when she noted occasional cramps in the left lower quadrant of the abdomen associated with constipation. The episodes of cramping last about 30 minutes each and are most severe in the hour following her meals. She has taken laxatives which have partially relieved her symptoms, but she has had a decreased appetite and 12-pound weight loss over the past four weeks. In addition, she has become increasingly fatigued over this period. When questioned about her bowel habits, she reported bright red blood in her stools and a smaller caliber (i.e. diameter) of stool over the past two weeks. She appeared fatigued and distressed. Head and neck exams were normal, as was her thorax. Palpation of the abdomen revealed a 10 x 10 cm mass and tenderness in the left lower quadrant. Hepatomegaly was noted, and a hard and slightly tender liver edge was felt in the right upper quadrant. Bowel sounds were noticeably reduced. Based on this information, which of the following conditions would you consider to be the most likely cause of the patient’s symptoms?